QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 01 Oct 2020 Station : New London,CT Latitude: 41 21.3N Country : USA Longitude: 072 05.2W JASL # : 744A Time Meridian: 075W (GMT - 5 hr) GLOSS # : none Originator #:8461490 NODC #: 74071201 Contributor : National Ocean Service (NOS) National Ocean. and Atmos. Administration (NOAA) N/OES22 SSMC4, STATION 7109 1305 East West Highway Silver Spring, MD. 20910-3233 Originator : NOS Original Data: analog (standard) digital (ADR, NGWLMS, MWWL) Instrmnt Type: 1) standard float and well gauge 1938-1974 2) analog-to-digital (ADR) recorder, float/wire 1975-1993 3) Aquatrak acoustic sensor/protective well, NOAA Next Generation Water Level Measuring System (NGWLMS) (1994-) 4) Design Analysis WaterLOG Microwave sensor (MWWL) radar gauge (2018-) Digitzd Intvl: hourly (standard); six-minute (digital) NGWLMS and MWWL sampling are three-minute averages Present Data : Hourly, daily, and monthly values obtained by: Hourly : The original digitizing interval was hourly (standard); spot sampling on the hour (digital) Daily : 119-point convolution filter (Bloomfield, 1976) centered on noon applied to the hourly data with respective periods of the 95, 50, and 5% amplitude points at 124.0, 60.2, and 40.2 hours Monthly: Simple average of all daily values; calculated if 7 or fewer days are missing Span of data : 12 Jun 1938 - 31 Dec 2019 Gaps > 1 mon : 01 Jan 1945 - 31 Jan 1945;09 Nov 1953 - 29 Dec 1953 01 Jan 1964 - 01 Oct 1964;01 Nov 1967 - 01 Dec 1967 01 Mar 1973 - 01 Apr 1973;27 Mar 1975 - 30 Apr 1975 01 Dec 1975 - 05 Jan 1976;14 Jun 1977 - 14 Sep 1977 04 Oct 1977 - 19 Jul 1978 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : Yes Distribution : 1938-2019 Refernce Levl: All heights have been referred to the station tide staff zero which is linked to fixed bench marks. While standard mechanical or ADR instrument was the primary gauge, leveling calibration factors were applied monthly based on tide staff comparisons. Comment : The daily and monthly means reveal no apparent reference level changes or trends. This site is called "New London, Thames River, CT". CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1938 54 264-269 none none 1939 100 none none none 1940 100 none none none 1941 100 none none none 1942 100 none none none 1943 100 none none none 1944 100 none none none 1945 87 1-31,215-221,223- none none 229,236-241 1946 100 none none none 1947 100 none none none 1948 100 none none none 1949 100 none none none 1950 100 none none none 1951 100 none none none 1952 100 none none none 1953 86 313-363 none none 1954 100 none none none 1955 100 none none none 1956 100 none none none 1957 100 none none none 1958 100 none none none 1959 100 none none none 1960 100 none none none 1961 95 1-3,22-38 none none 1962 100 none none none 1963 100 none none none 1964 25 1-275 none none 1965 100 none none none 1966 100 none none none 1967 88 132-136,305-335,337- (12)353-(19)353 none 338,359-365 (05)354-(14)354 1968 99 1 (01)270-(14)270 none 1969 96 194-197,202-210, none none 212-217 1970 100 none none none 1971 98 214-223 none 217,220-221,240 1972 100 none (21)361-(20)362 none 1973 83 2-32,60-91,130-131 (02)034-(21)034 none (05)092-(20)092 1974 100 none none none 1975 65 11-14,25-27,34-59, none none 82-120,244-273,335- 365 1976 97 1-5,59-60,213-215 (05)153-(19)153 59,223 1977 48 16-19,21-24,64-67, (11)035-(19)035 none 165-257,277-365 1978 44 1-200,259-264 none none 1979 89 43-51,215-220,229- (21)001-(05)002 none 231,277-279,286-288, (20)180-(04)181 295-299,314-330 1980 98 12-18 none none 1981 99 12-13 (22)310-(20)311 none 1982 99 299-300,308-310 (01)296-(20)296 none 1983 100 none none none 1984 98 47-52,105-106 (03)128-(11)128 none (01)143-(21)143 (09)257-(00)258 1985 87 34-60,164-182,192- (22)027-(13)028 none 195 (02)031-(20)031 1986 99 62-63 (05)064-(14)064 none 1987 100 none none none 1988 100 none (04)158-(21)158 none 1989 100 none (05)152-(12)152 none 1990 100 none none none 1991 100 none none none 1992 100 none none none 1993 99 268-269,361-363 (06)058-(14)058 none (21)218-(14)219 (00)265-(17)265 (05)270-(14)270 (02)273-(16)273 1994 97 16-17,39-44,58-62 (14)011-(03)012 none (09)035-(08)036 (07)046-(03)047 (08)048-(16)048 1995 99 269-270 (05)346-(18)346 none (06)347-(17)347 (07)348-(18)348 1996 100 none (00)163-(21)163 none 1997 100 none none none 1998 100 none none none 1999 100 none none none 2000 100 none none none 2001 100 none none none 2002 100 none (23)199-(17)200 none 2003 94 15-16,18-21,37-50, (19)016-(11)017 none 57-59,63-64,66-67, (04)021-(15)021 69-71 (14)073-(09)074 (01)195-(15)195 2004 95 15-16,19-22,23-34, (00)017-(09)017 none 356-357 (12)017-(09)018 (03)047-(15)047 (17)363-(02)364 2005 97 18-31 none none 2006 100 none none none 2007 100 none none none 2008 92 4-5,42-44,217-244 (01)358-(20)358 none 2009 100 none none none 2010 100 none none none 2011 97 357-365 none none 2012 97 357-366 none none 2013 100 none none none 2014 100 none none none 2015 96 182-197 none none 2016 100 none none none 2017 100 none none none 2018 100 none none none 2019 100 none none none